This invention relates generally to air conditioning systems. More particularly the invention relates to window room air conditioners wherein moisture removed from inside air is conducted to the outside section of the unit.
Warm air is frequently humid, i.e. it contains entrained water vapor. During operation of an air conditioning system in the cooling mode, the system refrigerant evaporator reduces the temperature of the air passing through it to below the dew point. In that condition, water vapor condenses on the evaporator. Some means must be provided to dispose of this condensate. In small unitary air conditioners, such as window room air conditioners, a common means to accomplish condensate disposal is by providing a condensate collection and drain path that communicates between the inside section and the outside section of the air conditioner. Condensate formed on the systems evaporator drains into a collector in the inside section and then flows to a collector located under the condenser fan in the outside section. The outside section condensate collector and the condenser fan or a slinger are arranged so that they will contact the condensate in the collector and sling it on to the hot surfaces of the system condenser where the condensate water evaporates. In most room air conditioners the outlet for the condensate water from the indoor to the outdoor section is a hole in a partition between the indoor and outdoor sections. The hole is typically located at the lowest level of the base pan of the air conditioner. In most room air conditioners such an arrangement has proved satisfactory. However with recent more compact and efficient design the situation has arisen where the outdoor section is actually pressurized by the units outdoor condenser fan. As a result of this some outside air may be caused to blow through the outlet hole from the outdoor section to the indoor section. Under such circumstances, this air may carry drops of water with it from the outdoor to the indoor section to the extent that the water collects in the basepan and overflows the flange of the basepan and leak out of the unit on the indoor side. Further, under severe rain and wind conditions water passage from the outside to the inside could occur.
It is an object of the present invention to prevent the back flow of water from the outside section to the inside section of an air conditioner through a passage which is provided for passage of condensate from the indoor to the outdoor section.
It is a further object of the present invention to allow unimpeded condensate flow from the inside to the outside in a simple and economical manner while preventing water being forced from the outside to the inside.